生草栽培与坡度对桂东北坡地果园地表径流氮磷流失的影响
李婷婷1,2, 韦彩会1, 董文斌1, 俞月凤1, 唐红琴1, 李忠义1, 何铁光1

(1.广西壮族自治区农业科学院农业资源与环境研究所, 南 宁 530007; 2.广西大学, 南 宁 530004)

生草栽培; 坡度; 总氮流失量; 总磷流失量

Effects of Sod Culture and Slope on Losses of Nitrogen and Phosphorus in the Surface Runoff of Orchards of Northeast Guangxi
LI Tingting1,2, WEI Caihui1, DONG Wenbin1, YU Yuefeng1, TANG Hongqin1, LI Zhongyi1, HE Tieguang1

(1.Agricultural Resources and Environmental Research Institute, Guangxi Academy of Agricultural Sciences, Nanning 530007, China; 2.Guangxi University, Nanning 530004, China)

sod culture; slope; total nitrogen loss; total phosphorus loss

备注

对桂东北坡地果园地表径流氮磷流失进行研究,为该区养分流失控制提供数据支撑和科学依据。在野外自然降雨条件下研究了不同坡度(即坡度为12°,23°,42°)金桔园间种雀稗(Paspalum thunbergii)和白花藿香蓟(Ageratum conyzoides)后果园氮、磷养分流失状况。结果表明:随着坡度升高,同一生草栽培的地表径流总氮、总磷、氨氮及硝态氮平均含量增加。相对于清耕处理,间种雀稗后金桔园地表径流总氮、总磷、氨氮及硝态氮流失量分别减少4.61%～24.55%,15.30%～26.49%,9.97%～48.03%和17.46%～96.46%。间种白花藿香蓟后地表径流总氮、总磷、氨氮及硝态氮流失量分别减少9.15%～16.17%,10.09%～13.16%,1.90%～33.19%和11.67%～19.41%。生草栽培、坡度及两者的交互作用对总氮和总磷流失量均有极显著的影响(p<0.001),生草栽培对地表径流氮磷流失量的抑制作用随着坡度升高而减弱,而坡度对地表径流氮磷流失量的增加作用则增强。雀稗对总氮和总磷流失量降低的相对贡献指数高于白花藿香蓟。随着坡度升高,同一生草栽培处理的土壤养分含量下降。同一坡度下雀稗控制养分流失效果优于白花藿香蓟,生草栽培的存在可在一定程度上削弱坡度对果园坡面氮磷流失的增加作用。
In order to provide data support and scientific basis for nutrient loss control in Northeast Guangxi, the losses of nitrogen and phosphorus in surface runoff of orchard were studied. Under the condition of natural rainfall in the field, Paspalum thunbergii and Ageratum conyzoides were intercropped in Kumquat orchards under different slope conditions(i.e.,12°,23°,42°), and the effects of the losses of two kinds of grass culture components were compared and analyzed. The results showed that, with the increase of slope gradient, the average contents of total nitrogen, total phosphorus, ammonia nitrogen and nitrate nitrogen in the runoff of the same life grass cultivation increased. Compared with clear ploughing, Paspalum thunbergii reduced the losses of total nitrogen, total phosphorus, ammonia nitrogen and nitrate nitrogen by 4.61%～24.55%, 15.30%～26.49%, 9.97%～48.03% and 17.46%～96.46%, respectively. The losses of total nitrogen, total phosphorus, ammonia nitrogen and nitrate nitrogen of Ageratum conyzoides were 9.15%～16.17%, 10.09%～13.16%, 1.90%～33.19% and 11.67%～19.41%, respectively. The effect of grass growth on the losses of total nitrogen and total phosphorus was significant(p< 0.001). With the increase of slope gradient, the inhibition of grass cultivation on the amount of nitrogen and phosphorus loss decreased, while the promotion of slope on the amount of nitrogen and phosphorus loss increased. The relative contribution index of Paspalum thunbergii to the losses of total nitrogen and total phosphorus was higher than that of Ageratum conyzoides. With the increase of slope gradient, the soil nutrient content of the same life grass decreased. The control effect of Paspalum thunbergii on nutrient loss was better than that of Ageratum conyzoides. The existence of grass cultivation can weaken the increasing effect of slope on the losses of nitrogen and phosphorus in surface runoff to some extent.